JP2000058188A - Waterproof coupler - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent water from infiltrating into a coupler housing through a gap between cores in a sheath part of a wire, in relation to a waterproof coupler mounted to an end of the wire having the sheath. SOLUTION: A gap between cores 2a is sealed by injecting a sealing compound (a) into a sheath part 2b. A sealing part 7 to secure a sealing property, when a grommet 6 deteriorates is formed by injecting the sealing compound (a) into a gap on the opening end side of a wire insertion hole 4a of a coupler housing 4 or gaps between sealing beads 6a on the outside periphery of the grommet 6 as well. A communicating passage 8 for making the inside of the sheath part 2b communicate with the sealing part 7 is formed in the sheath part 2b, so that the sealing compound (a) can be injected into the sealing part 7 and the sheath part 2b from an injecting hole 9 which is formed in the peripheral wall part of the wire insertion hole 4a.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a waterproof coupler mounted on an end of a covered electric wire.

[0002]

2. Description of the Related Art Conventionally, in this type of waterproof coupler, an end of an electric wire is liquid-tightly inserted into an electric wire insertion hole of a coupler housing through a grommet extrapolated to a covering portion of the electric wire, and an electric power inside the coupler housing is reduced. Water is prevented from entering the connection.

[0003]

In the above-mentioned conventional waterproof coupler, when a scratch or a crack is formed in the covering portion of the electric wire, a capillary phenomenon or a pressure difference between the inside and outside of the coupler causes a gap between the core wires of the electric wire to the electric connection portion. Water may enter.

SUMMARY OF THE INVENTION In view of the above, it is an object of the present invention to provide a waterproof coupler capable of ensuring waterproofness of an electric connection portion in a coupler housing even when water enters a covering portion of an electric wire. .

[0005]

Means for Solving the Problems In order to solve the above problems,
The present invention is a waterproof coupler to be attached to an end of a covered electric wire, wherein the end of the electric wire is inserted in a liquid-tight manner into an electric wire insertion hole of a coupler housing through a grommet extrapolated to the covered portion of the electric wire. In such a device, a sealant is injected into a covering portion at an end of the electric wire to seal a gap between core wires of the electric wire.

According to the present invention, even if a wound or a crack is formed in the covering portion of the electric wire, the gap between the core wires in the covering portion is sealed with the sealant, so that water does not enter through the gap between the core wires. In addition, the waterproofness of the electrical connection portion in the coupler housing is ensured.

In addition, the grommet is inserted into the electric wire insertion hole such that the tail end of the grommet enters inside the opening end of the electric wire insertion hole, and a sealing agent is injected into a gap on the opening end side of the electric wire insertion hole. Forming a seal portion for sealing the gap, or injecting a sealant between outer circumferential seal beads formed on the grommet to seal a gap between the inner wall surface of the wire insertion hole and the seal bead. If the portion is formed, even if the sealing property between the inner wall surface of the wire insertion hole and the grommet is deteriorated due to deterioration of the grommet or the like, water can be prevented from entering by the sealing portion, and the waterproofness is further improved.

In the case where a seal portion is formed in the gap on the opening end side of the wire insertion hole, a communication path is formed in the cover portion of the electric wire to communicate the inside of the cover portion with the seal portion. When a seal portion is formed in a gap between the inner wall surface of the insertion hole and the seal bead, the grommet and the covering portion of the electric wire may be provided with a communication passage communicating the inside of the covering portion with the seal portion. By injecting the sealant into the seal portion, the sealant can be injected into the coating portion. Further, if a sealant injection hole communicating with the seal portion is formed in the peripheral wall of the wire insertion hole, the end of the electric wire can be formed. The sealing agent can be injected into the seal portion and the coating portion from the outer periphery of the coupler housing without being disturbed by the electric wire in a state where the coupler is mounted on the portion, and the injection operation becomes easy.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. 1, reference numeral 1 denotes an electric device such as an electronic control unit, which is provided with a coupler 3 attached to an end of a covered electric wire 2 provided on a body of the electric device 1. Part 1a
And can be inserted freely.

The coupler 3 includes a coupler housing 4 and a plug 5 in the coupler housing 4. An end of the electric wire 2 is inserted into an electric wire insertion hole 4a of the coupler housing 4, and a core 2a of the electric wire 2 is formed. Is connected to the plug 5 by caulking or the like and the coupler 3 is inserted into the insertion portion 1a.
The plug 5 comes into contact with the spring terminal 1c on the substrate 1b inside,
The electric wires 2 are electrically connected to the substrate 1b.

As shown in FIG. 2, the end of the electric wire 2 is inserted into the electric wire insertion hole 4a in a liquid-tight manner through a grommet 6 extrapolated to the covering portion 2b of the electric wire 2. 5
A waterproof coupler that prevents water from entering an electrical connection portion such as a connection portion of the electric wire 2 or a contact portion between the plug 5 and the substrate 1b. The grommet 6 is made of rubber, and has a plurality of seal beads 6a formed on the outer periphery. The seal beads 6a adhere to the inner wall surface of the electric wire insertion hole 4a to secure the sealing property. In addition, a seal ring 1d is provided between the inner end surface of the insertion portion 1a and the end surface of the coupler housing 4 so as to prevent water from entering the container from the outer periphery of the coupler housing 4.

When the cover 2b of the electric wire 2 is scratched or cracked and water enters the cover 2b, the water flows into the gap between the core wires 2a of the electric wire 2 due to a capillary phenomenon or a pressure difference between the inside and outside of the coupler. Penetrates into the coupler housing 4 through the
The waterproofness of the electrical connection may be impaired. It should be noted that the core wire 2a of the electric wire 2 is actually not a plurality of wires as shown in FIG.
Since a small gap remains between the holes a, water permeates.

Therefore, in the present embodiment, the sealing agent a is injected into the covering portion 2b of the electric wire 2 to seal the gap between the core wires 2a, so that water can be prevented from entering through the gap. . As the sealant a, it is desirable to use a silicon-based permeable gel-like material.

In the present embodiment, the grommet 6 is inserted into the wire insertion hole 4a such that the tail end of the grommet 6 enters inside the opening end of the wire insertion portion 4a.
A sealant a is injected into a gap on the opening end side of the seal member a to form a seal portion 7 for sealing the gap. According to this,
Grommet 6 and wire insertion hole 4 due to deterioration of grommet 6, etc.
a of the sealing portion 7
This can prevent water from entering and further improve waterproofness.

In this case, it is possible to separately inject the sealing agent a into the inside of the covering portion 2b of the electric wire 2 and into the sealing portion 7, but this requires time and effort. A communication passage 8 is formed in the portion 2b to communicate the inside of the covering portion 2b with the sealing portion 7, and when the sealing agent a is injected into the sealing portion 7, the inside of the covering portion 2b is also sealed via the communication passage 8. The agent a is to be injected. Further, in the present embodiment, an injection hole 9 for a sealant communicating with the seal portion 7 is formed in the peripheral wall portion of the electric wire insertion hole 4a, and the seal portion 7 is not obstructed by the electric wire 2 from the outer peripheral side of the coupler housing 4. In addition, the sealing agent a can be injected into the coating portion 2b. Although the communication passage 8 is formed by a radial through hole formed in the covering portion 2b, the communication passage 8 may be formed by dividing the covering portion 2b and a gap between the divided portions.

FIG. 3 shows a second embodiment, in which the same members as those in the first embodiment are denoted by the same reference numerals.
The difference from the first embodiment is that a sealant a is injected between the seal beads 6a of the grommet 6 to form a seal portion 10 for sealing a gap between the inner wall surface of the wire insertion hole 4a and the seal bead 6a. In addition, the waterproofness of the seal portion 10 can be ensured even when the grommet 6 is deteriorated. Further, in the second embodiment, communication passages 8 and 11 for communicating the inside of the covering portion 2b and the seal portion 10 are formed in the covering portion 2b and the grommet 6 of the electric wire 2 and the peripheral wall portion of the electric wire insertion hole 4a. In addition, an injection hole 9 for the sealant a communicating with the seal portion 10 is formed, and the sealant a can be injected into the seal portion 10 and the inside of the covering portion 2b from the injection hole 9.

In the second embodiment, the grommet 6 has an inner circumferential annular groove 1 communicating with the communication passage 8 of the covering portion 2b.
1a and a radial through-hole 11b communicating the groove 11a with the seal portion 10 are formed, and the annular groove 11a and the through-hole 11b form a communication path 11, which is shown in FIG. As in the third embodiment, the grommet 6 may be divided, and the communication passage 11 may be formed by a gap between the divided portions.

Further, as in the fourth embodiment shown in FIG. 5, a discharge hole 12 communicating with the seal portion 10 may be formed in the peripheral wall portion of the wire insertion hole 4a in addition to the injection hole 9 for the sealant a. According to this, by bleeding air from the discharge port 12,
The sealant a can be filled in the seal portion 10 without leaving air.

[0019]

As is apparent from the above description, according to the present invention, water can be prevented from entering through the gap between the core wires in the covering portion of the electric wire, and the waterproofness is improved.

[Brief description of the drawings]

FIG. 1 is a diagram showing a use state of a coupler of the present invention.

FIG. 2 is a cutaway side view of the first embodiment of the coupler of the present invention.

FIG. 3 is a cutaway side view of a second embodiment of the coupler of the present invention.

FIG. 4 is a cutaway side view of a third embodiment of the coupler of the present invention.

FIG. 5 is a cutaway side view of a fourth embodiment of the coupler of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 2 Electric wire 2a Core wire 2b Coating part 3 Coupler 4 Coupler housing 4a Electric wire insertion hole 6 Grommet 6a Seal bead 7,10 Seal part 8 Communication path of coating part 9 Injection hole 11 Communication path of grommet

Claims (6)

[Claims] 1. A waterproof coupler mounted on an end of a covered electric wire, wherein the end of the electric wire is liquid-tightly inserted into a wire insertion hole of a coupler housing via a grommet extrapolated to a covered portion of the electric wire. A waterproofing coupler, wherein a sealing agent is injected into a covering portion at an end of an electric wire to seal a gap between core wires of the electric wire. 2. Inserting the grommet into the wire insertion hole such that the tail end of the grommet enters inside the opening end of the wire insertion hole, and injecting a sealant into a gap on the opening end side of the wire insertion hole. 2. The waterproof coupler according to claim 1, wherein a sealing portion for sealing the gap is formed. 3. The waterproof coupler according to claim 2, wherein a communication passage communicating the inside of the coating with the sealing portion is formed in the coating of the electric wire. 4. A seal portion for sealing a gap between an inner wall surface of the wire insertion hole and the seal bead by injecting a sealant between outer circumferential seal beads formed on the grommet. The waterproof coupler according to claim 1. 5. The grommet and a covering portion of the electric wire
The waterproof coupler according to claim 4, wherein a communication passage communicating the inside of the covering portion with the seal portion is formed. 6. The waterproof coupler according to claim 3, wherein an injection hole for a sealant communicating with the seal portion is formed in a peripheral wall portion of the electric wire insertion hole.